To learn Turkish for the beginning you have to start from Alphabetic and I think you're Arabic native speaker so I will suggest a good youtube channel to learn Turkish for Arabs and It's has a hundred lessons about grammar and reading ( The channel name is: تركيا جنة الارض) also about the pronunciation of these letters you can watch and listen to this video on youtube (watch?v=BWFLDvL5u3M) she explain it in a good way :)

you can start by watching Turkish movies with subtitle. after you hear Turkish words these letters also you will say easily.you should see how these are coming out form mouth and lips.its not hard dont worry. it's like this; ş=shh ç=ch.

I can suggest memrise and duolingo by the way they both have Turkish courses that is made by the them, not the members so especially Memrise's courses are pretty good